Liquid-fuel-burning apparatus



1,631,855 G. E. GOODRIDGE 4 LIQUID FUEL BURNING APPARATUS June 7, 1927.

Filed Feb, 2, 1927 2 ,Sheets-Sheet 1 G. E. GOODRIDGE LIQUID FUEL BURNING 4APPARATUS Jun-e 7, 1927.

, Filed Feb. 2. 1927 2 sheets-sneu 2 Patented4 June 7, 1927.

UNiTaD STA Tas PATENT oFF-ica.

GEORGE E. GOODRIDGE, OF READING, MASSACHUSETTS, ASSIGNOB T0 BALLARD SERVICE CORPORATION, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAS- SACHUSETTS. l

' LIQUTD-FUEL-BURNING APPARATUS.

Application led'February 2, 1927. Serial No. 165,387.

burner nozzle and the fuel delivery mecha.-

`nism to the combustion chamber of the" heater Fig. 2 is a central, sectional elevation on the line 2-2 in Fig. 1 taken through the burner nozzle, showing the parts on a somewhat larger scale; 0

Fig. 3 is a plan view on a still larger scale of the intermediatesupply chamber, showing the pumps and float control valve arranged therein; and

Fig. 4 is a sectional elevation taken on the Aline 4-4 in Fig. 3.

Referring to the drawings and to the einbodiment of the invention which is therein shown for illustrative purposes, the liquid fuel burner comprises a burner nozzle 11 operatively related to the combustion chamber 13 of any suitable or usual heating dep vice and connected to the burner supply pipe 15 arranged to discharge through the nozzle and into the combustion chamber an atomized mixture of oil or other liquid fuel with air or other gaseous substance, the. fuel being herein assumed, for purposes of illustration, to be oil.

To supply the burner, a main reservoir or supply tank of relatively large capacity is provided, which is indicated diagrammatically at 17 in Fig. 1, and is ordinarily located at a point away from the burner. An

intermediate, relatively small capacity, supply chamber, however, is provided located in proximity to the burner, there being provision for delivering oil to the supply chamber from the mainreservoir and for maintaining the oil in the supply chamber at an approximately constant level. In connection with the intermediate supply chamber there is here provided also a power driven delivery pum f drawing its supply from the supply cham er and adapted to deliver the commingled oil and gas through the delivery pipe 15.

Referring to the drawings, the small capacity supply chamber is in the form of a box-like casing 19, the bottom or bed plate 21 of which is extended at 23 to form an ad- ]acent support for the driving motor 25. The bed plate with its supported motor and casing is preferably mountedin close proximity to the burner nozzle 11.

For drawing the oil from the intermediate reservoir and supplying it to the supply pipe 15 a delivery pump is employed, the casing of which is indicated at 29. This is preferably of the rotary positive displacement type and may, for example, be ofthe construction shown in my co-pending application, Serial No. 120,061, the suction pipe being indicated at 31 and the pump. delivery being connected directly to the supply pipe 15.

As shown inthe drawings, pump 29, instead of being mounted with the motor on the extended bed plate 23, is herein shown as contained within the supply chamber itself and enclosed by the walls thereof and by the cover 33 ofthe casing, the frame members 35 and 37 of the pump being supported on the two lugs or pedes-V tals 39 and 41 which project upwardly from the bottom of the casing so that the working arts of the pump are raised above the normal level of the oil therein. rlhe driving .or rotor shaft 43 of the pump extends through an vOpening in one of the side walls of the casing, also well above the normal level of the oil, and connects externally with theV shaft of the motor 25 so as to be'driven thereby.

To permit the oil delivery pump 29 to draw from the supply chamber a mixture of air and oil, a suitable and preferably adjustable mixing device is provided. For this purpose the suction pipe 3l of the pump is bent downwardly sothat its end (see Fig. 2) dips below the normal level of the oil therein, and it is provided with an air and oil mixing device similar to that disclosed in my prior co-pending application, Serial No. 120,061, filed Jui 2i, i926.A Briefly, this involves the emp oyment of a sleeve valve 45 adapted to be adjustably turned by the dial 47 on the down-turned end of the fixed the delivery pipe 8l. The pipe 31 is provided with an oil admission orifice in the form of .a slot 49 cooperatively related to an opening 51 in the sleeve 45, so that by turning the latter an aperture of varying size may be made available for the suction of oil through the suction pi e 31.

To regu ate the amount of air admitted to the pipe 31, the latter is provided with an air orifice, and the surrounding sleeve 45 1s also provided with an overlapping orifice, both in the form of slots formed in the walls and side of the pipe and sleeve respectively. Cooperatively related to the aforesaid air orifice is an outer air valve 53 in the form of an outer sleeve having an overlapping slot-shaped orifice 55 and securedto a second dial 57. By turning the dial 57 the air adjusting valve or sleeve 53 may be set at different positions to vary the air opening through the pipe 31 and sleeve 45 and thereby to vary the amount of air admitted and to adjust the proportion of air and oil delivered by the pump to the burner. j

By mounting the delivery pump within the intermediate supply chamber and causing the same to be enclosed therein, not only is there obtained a simple and compact apparatus, but the operative parts which are required to draw the oil from the intermediate supply chamber, commiugle it with the air and deliver the commingled air and oil under pressure to the supply pipe 15, are all contained in and within the casing 19,.

and all drainage and leakage, which may occur at any of the joints or other parts of the apparatus with which the oil comes into contact, pass down into the oil reserve of the supply chamber and are drawn into the suction pump and delivered to the burner. All the moving 1parts thus handling the oil may be kept enc osed, reducing the audible mechanical noise arising from the apparatus, as Well as odors from the oil, and diminishing the fire risk, since no leakage from the apparatus can spread to the parts exterior to the supply chamber.

The openings through which the motor shalt 45, the supply pipe 15 and other parts extend may be packed if desired, but since they are Well above the normallevel of the oil, such clearance as occurs may be usefully employed to provide air passages for the air supply required by the air and oil mixing valve. Since this air passes always from the outside into the supply chamber, this not only tends to counteract any accidental leakage of oil through the openings, but also to prevent the initiation of any creeping lilm of oil therethrough.v

The approximately constant level of the oil within the supply chamber 19 may be maintained in various ways, butl herein I have provided a pump designed to deliver 'D11 from the main reservmr A17 mt@ the supply chamber, the same being herein employed in conjunction with a float controlled valve which is designed to. regulate the supply in accordance with the needs of the burner. This oil supply pump is also preferably of the rotary positive displacement type and may be of the construction described in my aforesaid co-pending application, Serial'No. 120,061.

As shown in the drawings, the oil supply pump, the casing of which is represented at 59, is also mounted within the box-like casing 19, being herein shown as fastened to the frame piece 35 ofthe delivery pump 29 and driven by and with the rotor shaft 43 of the delivery pump, so that the supply pump operates only with and during the operation of the main or delivery pump. Since the supply pump also is located within the sup 1y chamber, any drainage or leakage there rom will also pass into the body of liquid contained therein and delivered therewith to the burner.

The suction pipe 61 of the oil supply pump (seeFig. 3) is connected to a ilter 63 of any usual construction, but which tor convenience is herein shown as lsecured to the side of the casing 19. The filter in turn is connected through the supply pipe 65 with the main reservoir tank 17. When the pump is in operation, the oilis drawn from the main tank 17 through the supply pipe 65 to the filter 63 and thence through. the suction pipe 61 into the casing of the fuel supply pump, from which it is delivered to the discharge pipe 67.

The latter is joined to the T connection 69, also enclosed within the casing 19, the T having two branches, one of which is connected to the main tank or reservoir 17 by the return pipe 71, constituting a by-pass or back-flow for the excess oil over and above what is required to maintain the normal level in the chamber. The second branch of the T extends downwardly to a coupling 73 (see Fig. 4) which has a delivery passage 75 of relatively restricted cross sectional area. The passage 75 opens into a valve chamber 77 formed in the sleeve 79 threaded on the protruding end of the coupling, the sleeve 79 being supported or aligned by the bracket 81 formed on the inside of the walls of the chamber 19.

Within the valve chamber 77 there is provided a valve 83 connected to the vertically movable valvestem'85, the lower protruding end of which is connected to the forked end of the float lever 87, the latter being pivoted at 89 on the depending end of the sleeve and carrying at its opposite end a float 91, the position of which controls the vertical position ofthe valve 83. When the normal level of the oil in the supply chamber is reached, the float 91 assumes a position which depresses the valve 8 3 and causes its lower `face to press against the valve seat presented by the sleeve 79, thereby closing the delivery port 93, through which and the connecting lateral port 95 the oil is delivered to the supply chamber. Further supply of oil is thereby cut olf until the {ioat again drops. When the valve 83 is lowered against the seat, cutting ofi" the supply to the supply chamber.,

the excess of oil which is drawn from themain reservoir by the pump 59 passes back to the reservoir through the back-HOW pipe 71.

ln the described' embodiment of the invention l have also shown means whereby an excess supply of oil may be cut olf from the reservoir in the event that the float drops to some abnormallyy low position, such as might result from a punctured float. To this end the coupling 73 also presents to the upper face of the valve 83 a second seat 97 such that, when the valve is raised to its extreme upper position, due to an abnormally low position of the float, the supply of oil will also be cut olf. In the usual installation of burners of this class and with the customary automatic'devices provided, such cutting olf of the oil supply will result in soon extinguishing the burner flame due to failure of the oil and in automatically cutting out the driving motor for the pumps, thereby quickly calling attention to the defeet in the float.

The orifice 75 and the coupling 73 are preferably such as to admit the oil at a rate which will supply the maximum requirements of the burner, that is to say, at a rate which will ordinarily provide a slightly overrich mixture, the float controlled valve being relied on to cut this down slightly from time to time to maintain an approximately constant and normal level in the body of oil in the chamber. Since the pump 59, which is relied upon to supply the oil from the main reservoir to the supply chamber, operates only with and during the operation of the main pump, and since the air and oil mixing valve will operate to provide an approximately constant mixture under moderate variations in the height of the liquid in the supply chamber, the oat valve need loperate only to maintain an approximately and not Cil an exactly constant level. If there is a slight leakage at the valve, due to the fact that it is not tight or to the presence of dirt or other foreign matter between the valve and the seat, no harm can result. If there is a slight excess of oil added to the reservoir, due to leakage or imperfect action of the float valve, the main delivery pump will take care of such excess with but slight variation in the richness of the mixture and ther-'check vto this increment offered by the action of vthe float valve, even though imperfect, will soon restore the oil to its normal level.

When the motor. is4 cut out by the action of` the thermostat ordinarily lused in such installations, not only the delivery pump 29 stops operation, but also the supply pump 59, so that any further accession to the supply of oil in the supply chamber is 'instantly stopped.

Accordingly, through the use of the auxiliary supply pump 59 acting in conjunction with the main pump 29, it becomes unnecessary to provide an absolutely accurate, tight, float control valve for maintaining an ap proximately constant level in the supply chamber. y

To provide a more exact adjustment for the supply orifice v75, a device such as the adjusting screw 99 may be employed adapted more or less to restrict the orifice, the adj usting screw being initially set to meet the maximum requirements of the burner and then left in such adjusted position.

In the normal operation of the burner, the valve 83 is adjusted in such a position that it works in close approximation tothe' lower valve seat contained-within the casing 79 and will only move to press against the upper seat 97 in an abnormally low position of the float andone which is not encountered in the normal operation of the apparatus.

It will be seen from Figs. 1 and 2 that in the preferred embodiment of the invention both pumps, ltogether with the float-controlled valve andair and oil mixing valve, are enclosed within the `casing 19, which in turn is enclosed by the cover 33, so that all the moving parts and open passages which deal with or handle the oil are within such enclosed chamber, and all leakage and drainage therefrom pass down into the auxiliary oil supply. In conjunction with the described burner, I have also provided means for regulating and preheating the auxiliary air supply which is delivered to the Combustion chamber. To provide such air supply (see Figs. 1 and 2), the combustion chamber is provided with one or more (herein two) air admission openings presented by the boxlike casings 101 and controlled by the dampers 103, the casings 101 communicating with air ducts or passages 105 which extend beneath the bottom or floor of the combustion chamber to the back thereof, where they open into the return air passage 107. The latter extends forwardly beneath the combustion chamber to a port 109 approximately beneath the nozzle 11. The entering air therefore becomes preheated by its passage under the heated bottom lwalls of the combustion chamber, and the admission of the air in this fashion also tends more or less to reduce the roar or noise of the draught. The preheated air is then delivered through the port 109 immediately at or below the front of the burner nozzle.

When the thermostat acts to cut out the action of the motor 25 and the burner, the further and continued passa e of the air supply to the combustion cham er in its passage to the iues tends'to cool down the heater as it comes in contact with the heating coils or other heat transfer walls employed. I have accordingly provided means tending to cut 0H or reduce such supply of air when the burner ceases operation, such devices, however, acting to restore suchsup ply as soon as it is required by the lstarting up of the burner. For this purpose the dampers 103 are connected by the forked connection 111 to the link 113, the latter in turn being connected to the end of the weighted lever 115 pivoted at 117 on a bracket 119 carried by a casing 121 located above the supply chamber. The casing 121 is mounted on an upright pipe connection 123 which provides communication between the delivery pipe 15 and a diaphragmatic pressure device 125 contained within the casing 121. When the i delivery pump 29 starts into operation the pressure within the delivery pipe 15 is communicated to the diaphragmatic device 125 and this serves to raise the pin 127 which bears against the under side of the lever 115. This in turn lifts the lever and opens the dampers 103, providing a full airv supply tothe burner as soon as it starts into operation! On the other hand, when the operation of the pump ceases, and further air supply is not required 35' for the combustion chamber, the pressure within the diaphragmatic device drops and the weighted lever also drops, allowing the dampers 103 automatically to close and cut off further air supply. Accordingly, the air supplied to the burner is not only preheated by its passage beneath the combustion chamber and before it'reaches the region of combustion, but is automatically cut off from the combustion chamber when the oil supply is cut off, thereby preventing the loss of heat units which would otherwise be yielded up to the cooling current of air by the heat transfer walls and walls of the com bustion chamber, if the air supply c were allowed to persist.

While I have herein shown and described for the purposes of illustration one specific embodiment of the invention, it is to be understood that the same may be varied within wide limits and that the elements herein described or some of them may be arranged in various combinations other than those herein disclosed, all without departingl from the spirit of the invention.

I claim as my invention the following 1. A liquid fuel burning apparatus comprising a burner nozzle, a main fuel reservoir, an intermediate, enclosed chamber of relatively small capacity in proximity tov the burner nozzle, said chamber having an air admission opening and an air-supplied space in the upper part thereof, a fuel supply pump forwithdrawing fuel from the main fuel reservoir and having provision for delivering the same to the supply chamber, said supply pump having its discharge also connected to a return conduit leading back to the main reservoir to return the excess thereto, a float controlled delivery valve for regulating the delivery by said pump to the supply lchamber to maintain an approximately constant level therein below said airsupplied space, a main pump for delivering commingled air and liquid fuel through the burner nozzle, saidv sup-ply pum being connected to operate only with an during the operation of the main pump, and said main and supply pumps being enclosed within the supply chamber but raised above the level of the liquid fuel maintained therein sufficiently to prevent the yentrance of liquid fuel into the Working parts through the exposed joints thereof, a motor for driving said pumps located outside ofsaid enclosed chamber, a suction conduit for said main pump provided with an inlet orifice immersed below the level of the liquid fuel within the supply chamber and a second air orifice above the liquid fuel level and open to the air-supplied space of-said chamber,

whereby a commingled mixture of air and liquid fuel is drawn from said chamber into said main pump and delivered to the burner while the leakage from said pumps drains into the liquid fuel yin the bottom of the sup- ,ply chamber and is delivered by the main pump to the burner, the gases arising from the fuel being also drawn into the pump and prevented from escaping outside the chamber and whereby the available supply of fuel by said supplypump for said chamber is cut off when the burner ceases operation.

2. A liquid fuel burning apparatus comprising a burner nozzle, a main fuel reservoir, an intermediate, enclosedv chamber of relatively small capacity in proximity to the burner nozzle, said chamber having an air admission opening and an air-supplied space in the upper part thereof, a fuel supply pump for withdrawing fuel from the main fuel reservoir and having provision for delivering the same to the supply chamber, said supply pump having its discharge also connected to a return conduit leading back to the main reservoir to return the excess thereto, a float controlled delivery valve for regulating the delivery by said pump to the supply chamber' to maintain an approximately constant level therein below said air-supplied space, a main pump for delivering commingled air and liquid fuel through the burner nozzle, said supply pump being connected to operate only with and during the operation of the main pumo, and said main pump being enclosed within the supply chamber but raised above the level of the liquid fuel maintained therein sufficiently to prevent the entrance of liquid fuel into the working parts through the exposed joints thereof, a suction conduit for said main pump provided with an inlet orifice immersed below the level of the liquid fuel within the sup ly chamber and a second air orifice above tie liquid fuel level and open to the air-supplied space of said chamber, whereby a commingled mixture of air and liquid fuel is drawn from said chamber into said main pump and delivered to the burner while the leakage from said pump drains into the liquid fuel in the bottom of the supply chamber and is delivered by the main pump to the burner, the gases arising from the fuel being also drawn into the pump and prevented from escaping outside the chamber and whereby the available supply of fuel by said sup-ply pump for said chamber is cut off' when the burner ceases operation.

3. A liquid fuel burning apparatus coin-l suction conduit provided with an inlet orifice p immersed below the level of the liquid fuel in the supply chamber and 'a second air orifice between the liquid fuel 'level and the pump and open to the air-supplied space of the chamber, said supply pump being connected to operate only with and during the operation of the main pump, and said main and supply pumps being enclosed within the supply chamber, whereby leakage therefrom drains into the liquid fuel in the supply chamber.

4. A liquid fuel burning apparatus comprising a burner nozzle, a main' fuel reser voir, anintermediate, enclosed chamber of relatively small capacity in proximity to the burner nozzle, said chamber, having an air admission opening and an air-supplied space in the upper part thereof, a fuel supply pump for withdrawing fuel from the main fuel reservoir and having provision for delivering the same to the supply chamber, means for regulating the supply to maintain a substantially constant level therein, a main pump for delivering commingled air and liquid fuel through the burner nozzle,

' said supply pump being connected to operate only with and during the operation of the main pump, and said main and supply pumps being enclosed within the supply chamber but raised above the level of the liquid fuel maintained therein sufficiently to prevent the entrance of liquid fuel into the Working parts through the exposed joints thereof, a suction conduit for said, main pump provided with an inlet orifice immersed below the level of the liquid fuel within the supply chamber and a second air orifice above the liquid fuel level and open to the air-supplied space of said chamber, whereby a commingled mixture of air and liquid fuel is drawn from said chamber into sald main pump and delivered to the burner while the leakage from said pumps drains into the liquid-fuel in the bottom of the supply chamber and is delivered by the main pump to the burner, the gases arising from the fuel being also'drawn into the4 pump and prevented from escaping outside the chamber and whereby the available supply of fuel by said supply pump for said chamber is cut off when the burner ceases operation.A

5. A liquid fuel burning apparatus comprising a burner noz'zle, a main fuel reservoir, an intermediate, enclosed chamber of relatively small capacity in proximity to the burner nozzle, said chamber having an air admission opening and an air-supplied space in the upper part thereof, a fuel supply pump for withdrawing fuel from the main fuel reservoir and having provision for delivering the same to the Jsupply chamber,

means for regulating the supply to maintaina substantially constant level therein, a main ump for delivering commingled air and liquid fuel through the burner nozzle, said supply pump being connected to feperate only with and during the operation of the main pump, and said main pump being enlllf) closed within the supply chamber butraised -above the level of the liquid fuel maintained therein sufficiently to prevent the entrance of liquid fuel into. the working parts through the exposed joints thereof,.a suction conduit for said main pump provided with an inlet orifice immersed below the level of the liquid fuel within the supply chamber and a second air orifice above the liquid fuel level and open to the air-supplied space of 'said chamberl whereby a commingled mixture of air and liquid fuel is drawn from said chamber into said main pump and delivered to the burner while the leakage from said pump drains into the liquid fuel in the bottom of the supply chamber and is delivered by the main pump to the burner, the gases arising from the fuel being also drawn into the pump and prevented from escaping outside the chamber and whereby entrance of liquid fuel into the working parts thereof, said pump having a suction conduit provided with an inlet-orlice 1mmersed below the level of the liquid fuel 1n the supply chamber and a second orifice between the liquid fuel level and the pump connected to a source of gaseous supply whereby the pump supplies commingled gas and liquid fuel through its delivery conduit to the burner nozzle and anyk drainage or leakage therefrom passes to the liquid fuel in the bottom of the chamber and is delivered by the pump to the burner.

7. A liquid fuel burning apparatus comprising a burner nozzle, a main fuel reservoir, an intermediate supply chamber, a fuel supply pump for deliverlng liquid fuel to the supply chamber with means for regulating the supply to maintain a substantially constant level therein, a main atomizing pump for delivering commingled gas and liquid fuel through the burner nozzle, said lmain pump havlng a Asuction conduit immersed below the level of the liquid fuel in the supply chamber and provided with a1 second orifice between theliquid fuel level and the pump connected to a source of gaseous supply, an adjusting valve for proportioning the mixture of gas and'oil delivered by the pump, said supply pump being connected to operate only with and during the operation of the main pump, and said main and supply pumps being enclosed within the supply chamber -but raised above `the level of the liquid fuel maintained therein sufficiently to prevent the entrance of liquid fuel into the pumping parts thereof,

whereby any leakage from said pumps.

drains into the liquid fuel contained within the supply chamber.

8. A liquid fuel burning apparatus comprising a burner nozzle, a main fuel reservoir, an intermediate supply chamber of relatively small capacity, a fuel supply pump for delivering liquid fuel to the supply chamber, a float controlled valve for regulating the delivery by said \pump, a main atomizing pump for delivering commingled gas and liquid fuel through the burner nozzle, said main pump having a suction conduit immersed below the level of the liquidv fuel' in the suppy chamber and provided with a second ori ce between the liquid fuel level and the pump connected to a source of gaseous supply, said supply pump being connected to operate only with and during the operation of the main pump, and said main pump being enclosed within the supply chamber whereby leakage therefrom tends to pass into the liquid fuel in the supply chamber and to be drawn into and atomized by said main pump and fed to the burner nozzle.

9. A liquid fuel burning apparatus comprising a burner nozzle, a main fuel reservoir,'an intermediate supply chamber of relatively small-capacity, a fuel supply pump for withdrawing fuel from the main fuel reservoir and having provision for delivering the same to the supply chamber, said supply pump having its discharge also con-- nected to a return conduit leading back to the main reservoir to return the excess thereto, a float controlled delivery valve for regulating the delivery by said pump to the supply chamber to maintain an approximately' constant level therein, a main pump for delivering commingled air and liquid fuel through the burner nozzle, said supply pump being connected to operate only with and during the operation of the main pump, a motor for driving said pumps, a suction conduit for said main pump provided with an inlet orifice immersed below the level of the liquid fuel within the supply chamber, and a second air orifice above the liquid fuel level whereby a commingled mixture of air and liquid fuel is drawn into said chamber from said main pump and delivered to the burner.

10. A liquid fuel burning apparatus comprising a burner nozzle, a main fuel reservoir, an intermediate supply chamber of relatively small capacity, a fuel supply pump for withdrawing fuel from the main fuel reservoir and having provision for delivering the same to the supply chamber, a lioat controlled valve for regulating the delivery by said pump to the supply chamber to maintain an approximately constant level therein, a main pump for delivering commingled air and liquid fuel through the burner nozzle, said supply pump being connected to operate only with and during the operation of the main pump, a motor, for driving said pumps, a suction conduit for said main pump provided with an inlet orifice immersed below the level of the liquid I fuel within the supply chamber, and a second air orifice above the liquid fuel level whereby `a commingled mixture of air and liquid fuel is drawn into said chamber from said main pump and delivered to the burner.

In testimony whereof, I have signed my name to this specification.

GEORGE E. GOODRIDGE. 

